Improvement in stove-pipe elbows and in dies for producing the same



F. BOSH ERT.

Stovepipe Elbow.

Patented Feb. 13, 41866.

N. PETERS. PhmLimugmpher. washingmn. uc,

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FRnnRRtoK RosHnR'n oF New YORK, N. Y.

IMPROVEMENT IN STOVE-PIPE ELBOWS AND IN DIES FOR PRODUCING TiHE S'AME.

Speciti cation forming part of Letters Patent l\`o. 52,520, dated February 13, 1866.

10 all whom 'it may concern Beit known that I, FREDERICK BosHER'r, of the city, county, and State of New York, haveinvented a new and useful Improvement in Constructing` or Forming Elhows for Stove and other Sheet-,MetalPipea together with the Dies for Producing the Sameyand I do hereby declare that the following is a full, clear, andexact description ot' the same, reference being had to the necompanyin g drawings, making a part oi' this specitication, in which- Figure l is a longitudinal central section ot' an elbow constructed according' to my invention, a' x, Fig. 3, indicating the line ot' section;

.-Fig. 2, a longitudinal section ot' a portion ot' the same, taken in the line 'g/ y, Fig. 3; Fig. 3, a transverse section ot'. the same, t'aken in the line z z, Fig. 1.

Similar letters ot' reference indicate corresponding parts in the several figures.

This invention is designed to avoid the eX- pense in constructing the ordinary angular elbows for stove and other pipes by avoiding the miterjoint, and at the same time obtain one which will be more durable and possess the advantage of being adapted to suit the dii'er'ent positions in which it may be required to place the pipe.

'lhe invention consists in cutting the sheetmetal out ot' which the elbow is to be made in curved form, and then, by means of swaging between suitably-formed dies, giving a transverse semicircular form to the piece ot' sheet metal thus cut, so that when two such pieces are connected together they will form a quarter ot' a tubular cylindrical ring, the pieces otn sheet metal being swaged with recesses in them in order to avoid the breaking of the metal while being swaged, as hereinafter set forth.

To enable those skilled in the art to fully understand and construct my invention, l will proceed to describe itt In order to form the/elbow I take two pieces of sheet metal cut in the formv of a iiat ring, comprising a quarter, or rather more than a quarter, ot' a circle of greater or less diameter, as may be required. These sheet-metal plates are then, by means ot swaging, ,bent rtransversely in the form of a semicircle. so as to makev the longitudinal halves A A ot' a tube, and these two parts are connected together by lock-joints B B, as shown clearly in Fig. 3, said joints being formed by having radial tlanges a bent outward from the edges of one part or half ot' the tube A, and having a lip, b, heut on the edges ofthe other halt' to clasp and lock over the anges a. This joint may then be flattened down by another lap or turn over.

In order to prevent the metalv from rupturing or breaking during the swaging process, I swage the parts A A with recesses c in them, which `have a radial position in each part, as shown clearly in Fig. 1, said recesses extending from the inner or concave side ot' the tube, but not reaching the outer part. These recesses take up the superu'ous portion otl the metal at the inner portion ofthe parts or halves A A, and greatly facilitate the proper swaging and bending of said parts. rIhe shape or tgure oi' these recesses or indentations may be varied at pleasure;` but vit is necessary they should take up the superiiiitous metal, requiring very nice calculations in making the dies.

By this manner of constructing the elbows a serpentine elbow may be made by connecting the elbows as shown in red and blackin Fig. l; or acomplete circle or worm may be made. by connecting together a suitable number of them in proper position, a single elbow being used when a turn only in a right-angular direction in a pipe is required.

lhe plates may be swaged either when heated or in a cold state, according to the quality ot' the metal used. Inferior and brittle metal (sheet iron) will, of course, require to be heated.

The nature of my invention also consists more especially in so constructing my dies, male and female, or convex and concave, one to press the sheet metal within the other, that in forming a double curvature the surplus metal resulting from the same will be taken up and pressed into recesses or projections of any desirable shape, thus avoiding crimping and breaking of said sheet met-al at the curve or turn.

To enable others skilled in the art to make and use these dies, I will proceed to describe their construction and operation.

In the drawings, Fig. l, Plate 2, represents a top view of the concave or hollow die; Fio. 2, an under-side view of male or convex die; Fig. 3, a lateral section through both on line 'shape little difficulty is experienced by irreg ularities of surface, curves, Svc., but to all skilled in the art it is known the contrary is` the fact as to sheet-iron or other hard-metal plates, especially when swaged cold, giving rise to crimping and breaking, resulting from a surplus of metal. This I propose to absorb or take up, avoid crimping' or breaking, by pressing it in to figures of any desirable or fanciful shape, adding ornament to grace, at same time accomplishing a necessary result, a curved elbow or pipe being more pleasing to the eye, easier, and more cheaply constructed than an angular one.

A and B represent the two dies; C, the form of the plate, cut out before being pressed between them. In bad or brittle metal this plate should be heated to a proper degree before pressing. This, however, is not necessary in Russia sheet or other good metal.

Any screw-lever or other well-known press will answer to operate the dies after the plates are placed between them.

e andfare shoulders on the dies to prepare a ledge for thejoint by which to connect the halves after being pressed intoshape.

The process of completing the joint is well known to every worker in sheet metal, especially tinners or stove-pipe makers.

At the bend in'the dies will be seen on A small radial projections g, and corresponding recesses 7L in the other die. These may be re# versed, itl preferred, and the ligure varied; but I prefer those shown-graceful and easily made.

Generally one set or half-dies will answer by reversing one of the plates after pressing.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

l. An elbow for stoves and other sheet-nietal pipes, eonstructedof dat plates cut in the form of quarter rings of the required width,

and thenswaged transversely in semicircular form with the radial recesses to comprise the longitudinal halves` of a tubular cylindrical ring, substantially as set forth.

2 The dies A and B, for preparing hard sheet-metal plates for stove -pipe elbows or other curved pipes, having projections g and corresponding recesses L,.by which to take up or absorb the surplus metal resulting from a double curvature and avoiding crimpingor breaking of the same, snbstan tially as shown and described, and for the purpose set forth.

F. BOSHER'I'.

Witnesses M. M. LIVINGSTON, C. L. TOPLIFF. 

